As for being a skeptic - the phenomena we experience simply is. We may be able to "create our reality" in so far as we can encourage the world to mirror our dreams, but we exist in an energetic framework that is bigger than us and bigger than our ability to perceive. It would be ridiculous for lay people to expect their personal experience to prove or disprove quantum physics.
The spiritual phenomena in the shamanic experience is real and external. We don't create the Spirits by perceiving them. Instead, we are inviting them in, and asking for their involvement in our lives.

Our involvement with Spirits doesn't require another person to validate it. We stand in our understand that comes from direct experience with Spirit. We KNOW.